Currently, information techniques including personal computers are rapidly infiltrating personal lives. Overseas, all kinds of commercial products including books or antiques are easily purchased via Internet communication. This is very quick and simple, because a purchaser can purchase desired commercial products without taking the trouble to go to stores in town. However, since image information of commercial products being transmitted via Internet is limited and fixed, because they are information created and edited unilaterally by a seller, and the purchaser cannot enjoy commercial products from the viewpoint of the purchaser's desire.
A typical prior art is disclosed in Japanese Laid-Open Patent Application Publication No. Hei. 8-22498. In this prior art, three-dimensional images in a virtual world are pre-created by computer graphics. By utilizing the three-dimensional virtual world, an operator can overlook and approach various institutions and make comparison among the institutions as if the operator were normally purchasing products. In addition, images of displayed articles inside the institutions are offered by playing back video. When the operator finds a desired commercial product, its detailed information can be taken out.
In this prior art, a view point of a camera that takes images of the articles, i.e., an optical axis of the camera is predetermined by the seller, and therefore, the purchaser is incapable of selecting his/her desired view point, and hence cannot see images of back portions of the commercial products. Besides, the purchaser cannot observe the articles as serial images of the entire peripheries of the products. Further, some purchasers have their own scenarios of retrieval of the images of articles and move their eyes along a predetermined direction, so that the images can be played back only serially, although branching is possible. The purchaser needs to pre-construct the scenarios of the images of the articles. The need for imaging by the camera and modeling causes increased time and cost. In the case where the article is commercially available automobile, the purchaser cannot randomly access and select cases of an open state-mode, a half-open state-mode, and a closed state-mode of its door, and hence, cannot select and see the respective states of the articles. Moreover, the purchaser cannot perform operations of zoom up, i.e., getting closer, and zoom down, i.e., getting away, in real time.